1. Field of the Invention
The present invention relates to a snowmobile, wherein a structure of a reserve oil tank is provided for a dry sump type internal combustion engine that is mounted on the snowmobile and includes a particular layout structure of the tank.
2. Description of Background Art
A reserve oil tank of an internal combustion engine for a vehicle is generally disposed around the main body of the internal combustion engine. As one example of the reserve oil tank, in the case of an internal combustion engine mounted on a snowmobile, there is known a reserve oil tank for an internal combustion engine which is disposed at a side portion of the mounted internal combustion engine, i.e., at a side position, relative to the traveling direction of the vehicle. See, for example, Japanese Patent Laid-open No. 2002-266653, Page 5, FIG. 8.
The invention disclosed in Japanese Patent Laid-open No. 2002-266653 contains the description of the conditions of a structural portion on the vehicle body front side of a snowmobile. According to the description, a lubricating oil tank, or reserve oil tank, for an internal combustion engine mounted on the snowmobile is laid out at a side portion, relative to the traveling direction of the vehicle, around the internal combustion engine mounted on the snowmobile.
As above-mentioned, the lubricating oil tank for the internal combustion engine is generally laid out around the internal combustion engine, while being not limited to that on a snowmobile. However, more particularly in a vehicle with a limited vehicle body space as in the case of a small-type snowmobile, the layout of the lubricating oil tank, which occupies a comparatively large space, around the engine needs special contrivances in the selection of the layout position, tank shape, etc. due to the spatial factors thereof.
In the case where the layout of the lubricating oil tank for the internal combustion engine around the engine is achieved by disposing the tank at a position on the front or rear side of the crosswise-crankshaft engine, when the steering system is disposed on the front side of the engine as in the snowmobile according to the invention described in Japanese Patent Laid-open No. 2002-266653, the layout of the lubricating oil tank on the front side of the engine is further limited on a spatial basis. In addition, the layout of the oil tank on the rear side of the engine hinders the rider from approaching the engine, so that there again is a limitation from the viewpoint of achieving a compact design.